1. Field of Invention
The present invention relates generally to a seat assembly for use in an automotive vehicle, and more particularly, to a seat assembly having an inner occupant support frame which is movable from an occupant support position to an impact displacement position in response to rear impact loads on the seat assembly.
2. Description of the Related Art
Automotive vehicles include seat assemblies for supporting driver and passenger occupants within the vehicle. These seat assemblies include a generally horizontal seat cushion and an upright seat back. The seat back is commonly operatively coupled to the seat cushion by a recliner mechanism for providing pivotal adjustment of the seat back relative to the seat cushion between an upright seating position and a plurality of reclined positions. The vehicle also includes a seat restraint system operable with the seat assembly for maintaining the seat occupant in the seat upon the incident of a sudden impact upon the vehicle.
It is becoming increasing desirable to provide additional safety features within the vehicle and on the seat assembly for safely restraining the occupant in the seat and absorbing energy within the vehicle upon impact.
For example, the seat assembly often includes a head restraint connected to the upper portion of the seat back for protecting the occupant""s head during a vehicle accident. Head restraint may be vertically adjustable to accommodate various occupant heights and pivotally adjustable to position the head restraint close to the occupant head to assist in prevent xe2x80x9cwhiplashxe2x80x9d upon vehicle impact. The U.S. Pat. No. 5,378,043 to Viano et al. discloses a head restraint which is pivotally coupled to the seat back whereby upon a rear vehicle impact the head restraint moves in a forward direction toward the head of the seat occupant.
Seat assemblies may also include displacable seat mechanisms for displacing the entire seat assembly, or the entire seat back, rearwardly upon rear vehicle impact to maintain the occupant in the seat and absorb energy via the movement of the seat. Examples of displacable and energy absorbing seat assemblies are disclosed in U.S. Pat. Nos. 6,050,637; 6,109,692 and 6,062,642.
It remains desirable, however, to improve the retention and energy dissipation in a seat assembly to protect an occupant during a vehicle rear impact.
The present invention relates to a seat assembly for supporting a seat occupant in an automotive vehicle comprising a seat cushion for support the seat occupant on the seat assembly and a seat back extending longitudinally between a lower portion operatively coupled to the seat cushion and an upper portion for supporting the seat occupant in an upright position. The seat back includes an outer peripheral frame member, an inner occupant support frame operatively connected and supported by the outer peripheral frame member and movable from an occupant support position to an impact displacement position extending rearwardly of the outer peripheral frame member, and a displacable connection member operatively connecting the inner occupant support frame and the outer peripheral frame for maintaining the inner occupant support frame in the occupant support position during normal seat occupant use and for providing movement of the inner occupant support frame to the impact displacement position in response to a predetermined impact load exerted on the seat assembly.